There is a body of art in which corn kernels are popped on a conventional gas or electric stove. One of such device is seen in U.S. Pat. No. 3,144,194 to Cartright. A container cover for a popcorn package is shown by U.S. Pat. No. 3,054,680 of Mennen. In the Mennen patent is seen an aluminum foil inner cover which is preferably wrinkled and may be of a construction as in Robins et al U.S. Pat. No. 2,815,883 which will accommodate extension by expansion of a gaseous contents of food such as popcorn and popping oil. While Robins et al discloses a spiral round covering for popcorn containers, the device is shown as being made by hand. Subsequent thereto Mennen in U.S. Pat. No. 3,102,233 discloses apparatus for shaping metal foil suitable for use as an inner cover for a pan or container for popping corn. FIGS. 9-11 of that patent respectively show a sectional view of a food container having a formed foil cover, a sectional view illustrating in expanded condition the food container cover and the plan view of the formed food container cover. However, containers of the type just described are not suitable for use in microwave ovens where foil is prohibited. Accordingly, other types of containers for packages have been devised for shipping corn and popping same in a microwave oven. Illustrative thereof are U.S. Pat. No. 4,450,180 to Watkins which describes a paper container lined with a "greaseproof" paper liner and containing a charge of popcorn and fat in a small tubular portion of the package. It is intended that the corn charge within the bag sits in the bottom of a microwave oven when used for popping corn. U.S. Pat. No. 4,571,337 to Cage et al shows a paper bag containing a inner layer such as polyester, or more specifically polyethylene terephthalate instead of the "grease proof" paper layer of Watkins. Bohrer et al in U.S. Pat. No. 4,553,010 takes a slightly different approach. In Bohrer et al a paperboard box having on the bottom a metallized layer of polyethylene terephthalate as an interactive material with microwave energy is used as a "pop assist" to increase the popability of the corn.
Each of these packages for popping popcorn has its own disadvantage. For instance, the Watkins package with its greaseproof liner still permits staining of the outside package from the included shortening or oil. The Cage et al package, when unfolding, tends to strike the top of small microwave ovens and tilt on the side thereby popping only a small portion of the corn kernels therein. Bohrer presents to the user a disadvantage of having to open the package, remove at least a packet of corn and cooking oil, and often separate packets, opening said packet(s) and returning the contents thereof to the original package prior to the reassembly thereof and insertion into the microwave oven. Although Teich et al, U.S. Pat. No. 4,156,806, discloses a bowl having a downwardly directed conical bottom and means concentrating micro energy upon said conical bottom, Teich et al does not teach a device suitable for shipping and thereafter heating corn in a microwave oven.